I’ve noticed those digital locks on car doors only have five buttons but are numbered from one to ten (two numbers per key). So of course someone has done the math on this. There are 3125 combinations (5 key choices to the power of number of key presses which is generally 5 [5 to the 5th]). So they’ve calculated the 3129 digit sequence to open any car. You should only have to type in the whole sequence if the very last 5 digits are the combination. You could get lucky in the first hundred or two…

I read this here but I think I found it at Don’t Forward.